Method for preparing a porous polymer structure

Abstract

A polymer is dissolved in a first liquid or the polymer is brought into the liquid phase. To the solution are added particles which are insoluble in the first liquid, so that a suspension or dispersion results. The suspension or dispersion is then transferred into an excess of second liquid, in which both the polymer and the particles are insoluble. The second liquid is mixed vigorously and this results in a precipitate of the polymer with the particles encapsulated therein.

1 - 28 . (canceled)  
     
     
         29 . A method for preparing a porous polymer structure, comprising: 
 a) providing a first liquid with at least one polymer dissolved therein for the purpose of forming a first polymer liquid;    b) adding to the first polymer liquid at least one type of particle, insoluble in the first polymer liquid, for the purpose of forming a suspension or dispersion of particles in the first polymer liquid;    wherein by adding the suspension or dispersion to an excess of second liquid in which both the polymer and the particles are insoluble for the purpose of forming a precipitate having particles encapsulated therein in homogeneous distribution.    
     
     
         30 . The method as claimed in  claim 29 , wherein the formed precipitate is isolated from the second liquid.  
     
     
         31 . The method as claimed in  claim 30 , wherein the precipitate is dried.  
     
     
         32 . The method as claimed in  claim 31 , wherein the dried precipitate is processed into granules.  
     
     
         33 . The method as claimed in  claim 32 , wherein the granules are transferred at least once into a third liquid.  
     
     
         34 . The method as claimed in  claim 33 , wherein the third liquid is a solvent for the particles.  
     
     
         35 . The method as claimed in  claim 33 , wherein the third liquid is not a solvent for the polymer.  
     
     
         36 . The method as claimed in  claim 33 , wherein the third liquid is water.  
     
     
         37 . The method as claimed in  claim 33 , wherein the granules are isolated from the third liquid so as to obtain porous granules.  
     
     
         38 . The porous granules prepared with the method as claimed in  claim 33 .  
     
     
         39 . The porous granules as claimed in  claim 38 , wherein a porosity of 60 to 99% v/v is obtained by varying the particle size and the quantity of particles.  
     
     
         40 . The method as claimed in  claim 31 , wherein the granules and/or the precipitate are thermally processed and moulded.  
     
     
         41 . The method as claimed in  claim 40 , wherein the thermal process is chosen from the group comprising injection, extrusion, compression moulding, in-mould labelling casting or combinations thereof.  
     
     
         42 . The method as claimed in  claim 40 , wherein the moulded polymer structure is placed in at least a fourth liquid.  
     
     
         43 . The method as claimed in  claim 42 , wherein the fourth liquid is a solvent for the particles.  
     
     
         44 . The method as claimed in  claim 42 , wherein the fourth liquid is not a solvent for the polymer.  
     
     
         45 . The method as claimed in  claim 42 , wherein the fourth liquid is water.  
     
     
         46 . The method as claimed in  claim 42 , wherein the moulded polymer structure is isolated so as to obtain a porous moulded polymer structure.  
     
     
         47 . A porous moulded polymer structure prepared according to the method of  claim 42 .  
     
     
         48 . The porous moulded polymer structure as claimed in  claim 47 , wherein a porosity of 60 to 99% v/v is obtained by varying the particle size and the quantity of particles.  
     
     
         49 . The method as claimed in  claim 29 , wherein the first liquid is chosen from the group comprising the liquid polymer, organic and inorganic liquids or compositions thereof.  
     
     
         50 . The method as claimed in  claim 29 , wherein the particles are chosen from the group comprising organic compounds, inorganic compounds, salts, polymers, lipids, proteins, sugars or compositions thereof.  
     
     
         51 . The method as claimed in  claim 50 , wherein the particles are NaCl crystals.  
     
     
         52 . The method as claimed in  claim 50 , wherein the particles have a size of 0.001 to 5 mm.  
     
     
         53 . The method as claimed in  claim 29 , wherein the second liquid is chosen from the group comprising ethanol, methanol, isopropanol, ether, water or compositions thereof.  
     
     
         54 . A biomedical device prepared from the porous polymer structure as claimed in  claim 47 .  
     
     
         55 . A biomedical device prepared from the porous granules as claimed in  claim 38 .  
     
     
         56 . The method as claimed in  claim 50 , wherein the particles have a size of 0.1 to 1.5 mm.  
     
     
         57 . The method as claimed in  claim 50 , wherein the particles have a size of 0.1 to 1 mm.